Mechanical checking device for controlling the operation of spinning unit

ABSTRACT

A mechanical checking device for controlling the operation of a spinning unit for manufacturing yarn. The checking device includes a feeler which is freely movable from a first position in which it engages the yarn being pulled under tension from the spinning unit to a second position when such yarn breaks. Fibrous material is fed into the spinning unit by a driven roller, there being a controllable clutch interposed between such roller and a driving means. The clutch remains engaged when the feeler is in its first position; when the yarn breaks, however, the feeler acts mechanically effectively to disengage the clutch and to stop the feeding of fibrous material into the spinning unit.

limited States Patent Ladlislav at 51 E es-3 am EehZLWiZ inventors!lBrazda Ladislav, deceased, late of Cer veny Kosteiec, Czechoslovakia"'By [73] Assignee: Eiilen Znvotlytentilnilm Sti'ojirenstvi generalnirediteistvi, Liberec, Czechoslovakiaby said Prochazka, Kaulick, andOzdian [22] Filed: Feb. 25, 1970 [211 App]. No.: 13,9555

[30] Foreign Application Priority Data Mar. 6, 1969 Czechoslovakia..1636/69 [52] US. Ci ..57/tl3, 57/5895 [5i] lint. Cl DlllllltilIl/l6,DOlh 1/12 [58] lFieldoi'Seai-eh ..57/58.89,58.95,80,83,87

[56] References Cited UNITED STATES PATENTS 3,354,631 11/1967 Elias eta]. "57/5895 Primary Examiner-John Petrakes Attorney-Arthur O. KleinABSTRACT A mechanical checking device for controlling the operation of aspinning unit for manufacturing yam. The checking device includes afeeler which is freely movable from a first position in which it engagesthe yarn being pulled under tension from the spinning unit to a secondposition when such yarn breaks. Fibrous material is fed into thespinning unit by a driven roller, there being a controllable clutchinterposed between such roller and a driving means. The clutch remainsengaged when the feeler is in its first position; when the yarn breaks,however, the feeler acts mechanically effectively to disengage theclutch and to stop the feeding of fibrous material into the spinningunit.

re Claims, 5 Drawing Figures mmmmwm EWMEAH sum 1 0F 3 Enmzzmz 3,6A3Al3SHEU E OF 3 IN VE/VTORS Lad/310v Mllaslavp OCH/72K ATTORNEY PAIENIEmmem2 363A13 SHEET 3 OF 3 ATTORNEY MECHANICAL CHECKING DEVICE FORCONTROLLING THE UPlEIIATIUN F SPINNING UNIT The present inventionrelates to a mechanical checking device for controlling the operation ofa spinning unit for manufacturing yarn. The device may be used toadvantage, for example, in spinning yarn by a pneumomechanical method,particularly by means of an underpressure spinning chamber.

Checking devices of the type with which the present invention isconcerned control the spinning function ofthe spinning unit,particularly to start the feeding of fibrous material into the spinningunit when there is continuous withdrawal of the produced yarn from thespinning unit and stop the feeding of material into such unit in thecase of yarn breakage, when the danger of accumulation of fibrousmaterial in the spinning chamber arises. I

Various devices of this type are known which operate on the mechanical,mechano-electrical and electrical principles. There is also knownanother device which works on the principle of change of pneumaticconditions. All devices hitherto known have disadvantages, whichadversely affect the operating conditions in producing yarn, and whichreduce substantially the quality of the yarn in view of thenonuniformity of the knotting or connection points of the yarn afterbreakage. In the mechanical devices known hitherto, the maindisadvantage is their low sensitivity. The mechano-electrical devicesusually use microswitches, which are controlled either directly or bymeans of an interposed permanent magnet. These devices are verycomplicated in view of the high number of spinning units in the machine.Each spinning unit must be equipped with such a device; this makes theirmaintenance expensive. In the prior devices working on the electricalprinciple, because of the central control of the machine there are veryconsiderable requirements for the distribution of low voltage power,which requires the conductors to be of large cross section. Said devicesare also disadvantageous because of their high-energy input. A similarsituation is also present in devices working on the photoelectricprinciple. The devices working on the base of the change of pneumaticconditions are also not quite reliable, as pressure changes cause aconsiderable pollution of the spinning mechanism by drawing inimpurities. All the devices discussed above also have the one commondisadvantage that the impulses emitted therefrom have a longer delaythan admissible from the viewpoint of securing acceptable operationconditions.

The mechanism according to the present invention has the purpose tomitigate the above disadvantages and thus contribute to higher operationreliability and applicability of spinning machines, particularly but notexclusively those operating on the pneumomechanical principle ofmanufacturing yarn by means ofa spinning chamber operated underpressure.

The mechanism according to the present invention includes a freelyswingable feeler which is positioned in the yarn path, a mechanicaldriving coupling operated by the feeler in dependence of the presence orabsence of yarn, and an interposed driving mechanism for the feedingroller for feeding fibrous material into the spinning unit, the absenceof yarn in the yarn delivery path from the spinning unit stopping thefeeding of fibrous material into the spinning unit.

Further features of the mechanism according to the present invention aredescribed in the following specification and shown in the form ofexemplary embodiments in the accompanying drawings, in which similarparts are designated by the same reference characters.

FIG. 1 in the drawings shows a first embodiment of the mechanismaccording to the present invention in partial front elevation sectionduring normal operations;

FIG. .2 shows the embodiment of FIG. 1 upon yarn breakage;

FIG. 3 shows a second embodiment of the mechanism according to thepresent invention in partial front elevation section during normaloperation.

FIG. 4 is a detailed front elevation view of a third embodiment of themechanism according to the present invention during normal operation;and

FIG. 5 is a detailed view of the mechanism as shown in FIG. 4 upon yarnbreakage.

A machine for manufacturing yarn by a pneumomechanical method consistsof a large number of identical spinning units, each of which is equippedwith a mechanism according to the present invention. The drawings andthe specification are limited to the showing and description of only onemechanism, certain parts of the spinning units, which are not directlyrelated to the embodiment of this mechanism, not being shown forsimplicity of illustration and description.

As is evident from the above, three embodiments of mechanisms inaccordance with the invention are illustrated and described here. Thefirst embodiment is shown in FIGS. l and 2, the second in FIG. 3, andthe third in FIGS. Al and 5.

The mechanism according to the present invention shown in FIG. I and 2consists of a feeler I, mounted freely swingably about a pivot pin 2mounted on a fixed support. A further, cross arm la of the feeler 1 isin contact with yarn 3, which comes out from the withdrawing tube 4 of aspinning unit (not shown) and is withdrawn in the direction of arrow S,by a pair of withdrawing rollers 5, 6. On the main driving shaft 7 ofthe machine are firmly fixed tooth wheels or gears (one shown) 8 in anumber corresponding to the number of spinning units on the machine. Thetoothed wheel 8 of each spinning unit is in mesh with the drivingpart'of the securing coupling or clutch of the respective checkingdevice. Each such device includes a gear 9 mounted freely rotatably onthe shaft 10 and pressed into engagement with the driven plate part llof the coupling by means ofa coil compression spring I6, which issecured on the shaft 10 by a cup 17 and a nut 17a screwed to shaft 10.The plate part 11 of the coupling is. affixed to the shaft 10, which ismounted in bearings 12 and provided at its left-hand end with a gear 13,which is in mesh either directly or through another gear element (notshown) with a gear 14, which is connected with a feeding roller 15 forfeeding fibrous material into the respective spinning in the directionof arrow 5 In the embodiment as shown in FIGS. 1 and 2, the driving part9 of the clutch is made such that its front or left-hand surface isprovided with semicylindrical recesses into which are insertedcylindrical elements 18, which connect the driving part 9 of the clutchwith the driven part II by means of recesses in the right-hand face ofthe driven part Ill into which the cylindrical elements 18 fit. Insteadof being cylindrical, the connecting elements I18 may be balls, cones,or of other suitable shape.

In the exemplary embodiment shown in FIG. 3 the engagement surfaces ofboth the driving part 9 and the driven part ll of the securing couplingare provided with mutually engaged annular detents 22, thus forming atooth coupling.

In the exemplary embodiments of FIGS. 1 and 2, and of FIG. 3, of themechanism according to the present invention, as specified above andshown in the accompanying drawings, one of the further surfaces of thedriven part II (or 11') of the securing coupling, i.e., either the frontsurface 21 (as here shown) on the opposite side or the circumferentialsurface provided with a ratchet toothing, into which the shorter arm lbof feeler l is engaged in the case of breakage of the yarn 3 which iswithdrawn from the spinning unit arm lb, functions as a pawl.

The mechanism according to the present invention works as follows:

The yarn 3, produced in the respective spinning unit, comes out of thewithdrawing tube 4, and is scanned on its path towards the withdrawingrollers 5,6 which withdraw said yarn in the direction of arrow 3,, to awinding mechanism (not shown), by an arm 1a secured to the longer arm offeeler l. The said feeler I is held by the tensioned yarn 3 at aposition, at which its shorter arm lb is out of engagement with theratchet surface 21 of the driven part II of the clutch. The main shaft 7turns, rotation of the shaft 7 being transmitted by the gear 8 mountedthereon to the freely rotatable driving part 9 of the clutch on theshaft 10. Gear 9 is pressed by spring 16 into engagement with the drivenpart 11 of the clutch through the connecting elements 18 and recesses(FIG. 1) or over the toothing 22 of the two parts of the securingcoupling (FIG. 3). By pressure of the driving part 9 against the drivenpart 11 of the clutch said driven part is driven in the direction ofarrow S a andthus drives the shaft and the gear 13 fixed thereon. Thistransfers the rotary motion to the gear 14 and therefrom to the feedingroller 15, which thereupon feeds fibrous material into the associatedspinning unit.

If for any reason yarn breakage occurs (FIG. 2) yarn 3 no longer thruststhe longer arm of feeler 1 clockwise. Because of this, the feeler 1swings out with its own weight in the counterclockwise direction S andthe bottom end of the shorter arm 1b of feeler 1 engages the nearesttooth of the ratchet surface 21 of the driven part 11 of the clutch,thus effectively disengaging the clutch and preventing its furtherrotation by the driving part 9 and shaft 10 in the direction 5 The gear13 thus stops transmitting motion to the tooth wheel 14, and therotation of the feeding roller 15 is accordingly stopped. Thus thefeeding of fibrous material into the respective spinning unit isstopped. The part 9 of the clutch is rotatably driven by shaft 7; innormal operation part 9 drives part 11, shaft 10, gears 13, 14, and roll15 through the clutch 9, 11 when rotation of part 11 is stopped, asabove described, the connecting elements 18 repeatedly fall into andride up out of the confronting recesses in part 11. The force ofengagement between the lower arm lb of feeler 1 on the ratchet surface21 of the driven part 11 varies, due to the described sliding of theconnecting means between the two parts of the coupling. Such forceattains its minimum immediately after the elements 18 have ridden up outof the recesses in part 11. At any of such moments the feeler 1 can beeasily released, after the yarn breakage had been removed whereupon thedriven part 11 of the clutch is again released and starts moving in thedirection S The feeding of fibrous material into the spinning unit isresumed, the drive proceeding through shaft 10, gears 13 and 14, and thefeeding roller 15.

In the exemplary embodiment as shown in FIGS. 4 and 5, the shorter armlb of feeler 1 forms a control element, which is connected with a pawl19 mounted with one of its ends also swingably about point 2. The upperend ofa flat leaf spring 20 presses against pawl 19; said spring isfastened at its lower end to a part 2011 of the body of the associatedspinning unit.

In the exemplary embodiment shown in FIGS. 4 and 5, the feeler I isswung out, in the case of yarn breakage, by its own weight in acounterclockwise direction 8,. The lower end lb of feeler 1' stopsacting upon the pawl 19 against the thrust of leaf spring 20, whereuponthe pawl 19 is pressed by said spring 20 into a tooth of the ratchetsurface 21 of the driven part 11 of the clutch. After the breakage ofyarn 3 has been removed, the feeler 1' is tilted over in a clockwisedirection, opposite to S in such manner, as to be in contact with yarn3. The lower arm 1'b of feeler 1' now engages the pawl 19; the force ofthis impact releases pawl 19, against the force of spring 20, from thetooth of the ratchet surface 21 of the driven part 11 of the clutch.Part 11 is now released for further movement in the direction S so thatthe feeding of fibrous material into the associated spinning unit isresumed by the drive through shaft 10, gears 13 and 14, and feedingroller 15.

The advantage of the mechanism according to the present inventionconsists particularly in its simple construction, as well as in itsimmediate reaction to yarn breakage and its immediate restarting afterremoval of the yarn breakage. Any delay caused by dependence uponcertain electric elements,

e.g., relays, or the energizing of the magnetic coupling etc., iseliminated. Yarn produced by the apparatus of the invention ischaracterized by its greater uniformity.

Although the invention has been illustrated and described with referenceto the preferred embodiments thereof, it is to be understood that it isin no way limited to the details of such embodiments but is capable ofnumerous modifications within the scope of the agpended claims.

What is claime is:

1. In an apparatus having a yarn spinning unit, driven rotatable meansfor feeding fibrous material into the spinning unit, and means forwithdrawing spun yarn from the spinning unit, the improvement whichcomprises a mechanical checking device including a movable feelernormally held in a first terminal position by engagement of the feelerwith unbroken spun yarn being fed from the spinning unit, the feelerbeing movable to a second terminal position upon the breakage of saidspun yarn, a driving means, a normally engaged clutch interposed betweenthe driving means and the rotatable driven means for feeding fibrousmaterial into the spinning unit, and means operated by the feeler uponmovement of the feeler toward its second terminal position foreffectively disengaging the clutch and thereby stopping the means forfeeding fibrous material into the spinning unit.

2. A mechanical checking device according to claim 1, wherein the feeleris a lever freely swingable about a pivoted axis, the feeler having ayarn engaging portion adjacent its outer end.

3. A mechanical checking device according to claim 1, wherein the clutchhas a driving and a driven part, means yieldingly holding the drivingand driven means together in driving engagement, the clutch beingeffectively disengaged when the driven part is held from rotation whilethe driving part continues to rotate, and the means operated by thefeeler holds the driven part of the clutch from rotation upon movementof the feeler toward its second terminal position.

4. A mechanical checking device according to claim 3, comprising aratchet and a pawl for selectively retaining the driven part of theclutch from rotation, the ratchet being drivingly connected to thedriven part of the clutch, and the pawl being operated by the feeler.

5. A mechanical checking device according to claim 4, wherein the pawlis connected to the feeler.

6. A mechanical checking device according to claim 4, wherein the pawlis directly connected to the feeler so as to move therewith.

7. A mechanical checking device according to claim 4, comprisingresilient means constantly urging the pawl into engagement with theratchet, and means operated by the feeler when the feeler is in itsfirst terminal position for holding the pawl from engagement with theratchet against the opposition of the resilient means.

8. A mechanical checking device according to claim 7, wherein the feelerand pawl are connected by a common fixed pivot pin about which theyoscillate, and wherein the means for holding the pawl from engagementwith the ratchet comprises an arm on the feeler which engages andretracts the pawl from the ratchet as the feeler moves from its firsttoward its second terminal position.

9. A mechanical checking device according to claim 1, wherein the clutchis a coupling having releasably engaging toothed parts.

10. An apparatus according to claim 1, wherein the spinning unitmanufactures yarn by a pneumomechanical method, said unit including aspinning chamber operating under pressure.

bilhltl r.

1. In an apparatus having a yarn spinning unit, driven rotatable meansfor feeding fibrous material into the spinning unit, and means forwithdrawing spun yarn from the spinning unit, the improvement whichcomprises a mechanical checking device including a movable feelernormally held in a first terminal position by engagement of the feelerwith unbroken spun yarn being fed from the spinning unit, the feelerbeing movable to a second terminal position upon the breakage of saidspun yarn, a driving means, a normally engaged clutch interposed betweenthe driving means and the rotatable driven means for feeding fibrousmaterial into the spinning unit, and means operated by the feeler uponmovement of the feeler toward its second terminal position foreffectively disengaging the clutch and thereby stopping the means forfeeding fibrous material into the spinning unit.
 2. A mechanicalchecking device according to claim 1, wherein the feeler is a leverfreely swingable about a pivoted axis, the feeler having a yarn engagingportion adjacent its outer end.
 3. A mechanical checking deviceaccording to claim 1, wherein the clutch has a driving and a drivenpart, means yieldingly holding the driving and driven means together indriving engagement, the clutch being effectively disengaged when thedriven part is held from rotation while the driving part continues torotate, and the means operated by the feeler holds the driven part ofthe clutch from rotation upon movement of the feeler toward its secondterminal position.
 4. A mechanical checking device according to claim 3,comprising a ratchet and a pawl for selectively retaining the drivenpart of the clutch from rotation, the ratchet being drivingly connectedto the driven part of the clutch, and the pawl being operated by thefeeler.
 5. A mechanical checking device according to claim 4, whereinthe pawl is connected to the feeler.
 6. A mechanical checking deviceaccording to claim 4, wherein the pawl is directly connected to thefeeler so as to move therewith.
 7. A mechanical checking deviceaccording to claim 4, comprising resilient means constantly urging thepawl into engagement with the ratchet, and means operated by the feelerwhen the feeler is in its first terminal position for holding the pawlfrom engagement with the ratchet against the opposition of the resilientmeans.
 8. A mechanical checking device according to claim 7, wherein thefeeler and pawl are connected by a common fixed pivot pin about whichthey oscillate, and wherein the means for holding the pawl fromengagement with the ratchet comprises an arm on the feeler which engagesand retracts the pawl from the ratchet as the feeler moves from itsfirst toward its second terminal position.
 9. A mechanical checkingdevice according to claim 1, wherein the clutch is a coupling havingreleasably engaging toothed parts.
 10. An apparatus according to claim1, wherein the spinning unit manufactures yarn by a pneumomechanicalmethod, said unit including a spinning chamber operating under pressure.